{ ipv4
, ipv6
, config
, optionalString
, concatStringsSep
, factsGenerator
, mapAttrsToList
, ...
}:
let
  hosts = {
    mobi = "10.23.42.23";
    sterni = "10.23.42.24";
    bobi = "10.23.42.25";
    pepe = "10.23.42.26";
    cream = "10.23.42.27";
    chungus = "10.23.42.28";
    cherry = "10.23.42.29";
    robi = "10.23.42.111";
    orbi = "10.23.42.100";
  };
  subDomains = {
    # orbi
    "transmission2.orbi" = hosts.orbi;
    "sonarr.orbi" = hosts.orbi;
    "radarr.orbi" = hosts.orbi;
    "prowlarr.orbi" = hosts.orbi;
    "photoprism.orbi" = hosts.orbi;
    # robi
    "grafana.robi" = hosts.robi;
    "loki.robi" = hosts.robi;
    "prometheus.robi" = hosts.robi;
    "sync.robi" = hosts.robi;
    "transmission.robi" = hosts.robi;
    "transmission2.robi" = hosts.robi;
    "sonarr.robi" = hosts.robi;
    "radarr.robi" = hosts.robi;
    "tdarr.robi" = hosts.robi;
    "prowlarr.robi" = hosts.robi;
    "jellyseerr.robi" = hosts.robi;
    "unmanic.robi" = hosts.robi;
    # chungus
    "de.tts.chungus" = hosts.chungus;
    "en.tts.chungus" = hosts.chungus;
    "flix.chungus" = hosts.chungus;
    "git.chungus" = hosts.chungus;
    "grafana.chungus" = hosts.chungus;
    "loki.chungus" = hosts.chungus;
    "prometheus.chungus" = hosts.chungus;
    "s3.chungus" = hosts.chungus;
    "minio.chungus" = hosts.chungus;
    "sync.chungus" = hosts.chungus;
    "tdarr.chungus" = hosts.chungus;
    "tts.chungus" = hosts.chungus;
    "paperless.chungus" = hosts.chungus;
  };
  network = "private";
  Ed25519PublicKey = machine: (builtins.readFile "${config.clanCore.clanDir}/machines/${machine}/facts/tinc.private.ed25519_key.pub");
  Ed25519PublicKeyFile = machine: "${config.clanCore.clanDir}/machines/${machine}/facts/tinc.private.ed25519_key.pub";
in
{
  networking.firewall.trustedInterfaces = [ "tinc.${network}" ];

  clanCore.facts.services.tinc_private = factsGenerator.tinc { name = "private"; };

  services.tinc.networks = {
    ${network} = {
      ed25519PrivateKeyFile = config.clanCore.facts.services.tinc_private.secret."tinc.private.ed25519_key.priv".path;
      interfaceType = "tap";
      extraConfig = ''
        LocalDiscovery = yes
      '';
      hostSettings = {
        mobi = {
          subnets = [{ address = hosts.mobi; }];
          settings.Ed25519PublicKey = "X5sp3YYevVNUrzYvi+HZ2iW5WbO0bIb58jR4jZFH6MB";
        };
        bobi = {
          subnets = [{ address = hosts.bobi; }];
          settings.Ed25519PublicKey = "jwvNd4oAgz2cWEI74VTVYU1qgPWq823/a0iEDqJ8KMD";
        };
        cream = {
          subnets = [{ address = hosts.cream; }];
          settings.Ed25519PublicKey = Ed25519PublicKey "cream";
        };
        cherry = {
          subnets = [{ address = hosts.cherry; }];
          settings.Ed25519PublicKey = Ed25519PublicKey "cherry";
        };
        chungus = {
          subnets = [{ address = hosts.chungus; }];
          settings.Ed25519PublicKey = Ed25519PublicKey "chungus";
        };
        orbi = {
          addresses = [{ address = "95.216.66.212"; }];
          subnets = [{ address = hosts.orbi; }];
          settings.Ed25519PublicKey = Ed25519PublicKey "orbi";
        };
      };
    };
  };

  systemd.network.enable = true;
  systemd.network.networks.${network}.extraConfig = ''
    [Match]
    Name = tinc.${network}
    [Link]
    # tested with `ping -6 turingmachine.r -s 1378`, not sure how low it must be
    MTUBytes=1377
    [Network]
    ${optionalString (ipv4 != null) "Address=${ipv4}/24"}
    ${optionalString (ipv6 != null) "Address=${ipv6}/28"}
    RequiredForOnline = no
    LinkLocalAddressing = no
  '';

  networking.extraHosts = concatStringsSep "\n" (mapAttrsToList (name: ip: "${ip} ${name}.${network}") (hosts // subDomains));

}